Spring Steel Strip for Roller Shutter Doors 1.Material: 65, 70, 75, 85, 65Mn, etc 2. ... .Width:30mm-355mm Specification of Spring Steel Strip for Roller Shutter Doors :1.Material: 65, 70, 75, 85, 65Mn, 55SiMnV, 60Si2MnA ... its original shape without deforming.7.We can offer a sample for your testing.8.Application: Spring Steel is widely in ...